Alterações da Actividade Autonómica Durante o Teste de Inclinação em Doentes com Fibrilhação Auricular Paroxística: Análise com Wavelets

The autonomic nervous system (ANS) is known to be an important modulator in the pathogenesis of paroxysmal atrial fibrillation (PAF). Changes in ANS control of heart rate variability (HRV) occur during orthostatism to maintain cardiovascular homeostasis. Wavelet transform has emerged as a useful tool that provides time-frequency decomposition of the signal under investigation, enabling intermittent components of transient phenomena to be analyzed. AIM: To study HRV during head-up tilt (HUT) with wavelet transform analysis in PAF patients and healthy individuals (normals). METHODS: Twenty-one patients with PAF (8 men; age 58 +/- 14 yrs) were examined and compared with 21 normals (7 men, age 48 +/- 12 yrs). After a supine resting period, all subjects underwent passive HUT (60 degrees) while in sinus rhythm. Continuous monitoring of ECG and blood pressure was carried out (Task Force Monitor, CNSystems). Acute changes in RR-intervals were assessed by wavelet analysis and low-frequency power (LF: 0.04-0.15 Hz), high-frequency power (HF: 0.15-0.60 Hz) and LF/HF (sympathovagal) were calculated for 1) the last 2 min of the supine period; 2) the 15 sec of tilting movement (TM); and 3) the 1st (TT1) and 2nd (TT2) min of HUT. Data are expressed as means +/- SEM. RESULTS: Baseline and HUT RR-intervals were similar for the two groups. Supine basal blood pressure was also similar for the two groups, with a sustained increase in PAF patients, and a decrease followed by an increase and then recovery in normals. Basal LF, HF and LF/ HF values in PAF patients were 632 +/- 162 ms2, 534 +/- 231 ms2 and 1.95 +/- 0.39 respectively, and 1058 +/- 223 ms2, 789 +/- 244 ms2 and 2.4 +/- 0.36 respectively in normals (p = NS). During TM, LF, HF and LF/HF values for PAF patients were 747 +/- 277 ms2, 387 +/- 94 ms2 and 2.9 +/- 0.6 respectively, and 1316 +/- 315 ms2, 698 +/- 148 ms2 and 2.8 +/- 0.6 respectively in normals (p < 0.05 for LF and HF). During TF1, LF, HF and LF/ HF values for PAF patients were 1243 +/- 432 ms2, 302 +/- 88 ms2 and 7.7 +/- 2.4 respectively, and 1992 +/- 398 ms2, 333 +/- 76 ms2 and 7.8 +/- 0.98 respectively for normals (p < 0.05 for LF). During TF2, LF, HF and LF/HF values for PAF patients were 871 +/- 256 ms2, 242 +/- 51 ms2 and 4.7 +/- 0.9 respectively, and 1263 +/- 335 ms2, 317 +/- 108 ms2 and 8.6 +/- 0.68 respectively for normals (p < 0.05 for LF/HF). The dynamic profile of HRV showed that LF and HF values in PAF patients did not change significantly during TM or TT2, and LF/HF did not change during TM but increased in TT1 and TT2. CONCLUSION: Patients with PAF present alterations in HRV during orthostatism, with decreased LF and HF power during TM, without significant variations during the first minutes of HUT. These findings suggest that wavelet transform analysis may provide new insights when assessing autonomic heart regulation and highlight the presence of ANS disturbances in PAF.

Actinomicose Mandibular Crónica. Implicações Anestésicas e Infecciosas: a Propósito de um Caso Clínico

Doente do sexo feminino, 18 anos, raça negra, natural da Guiné-Bissau, com quadro clínico com 8 anos de evolução, de sinais inflamatórios ao nível de ambos os ângulos da mandíbula, com nódulos palpáveis e drenagem espontânea de material aquoso não purulento, após exodontia de molar mandibular. Para diagnóstico definitivo foi colocada indicação para biópsia mandibular sob anestesia geral. Na avaliação pré-operatória destacava-se uma via aérea previsivelmente muito difícil: mallampati IV, micrognátia com abertura da boca muito limitada (1 cm), distância tiromentoniana < 6 cm e mobilidade cervical limitada, pelo que se programou intubação endotraqueal guiada por fibroscopia. Procedeu-se à intubação nasotraqueal guiada por fibroscopia com tubo 7,0 com cuff, sob sedação endovenosa com midazolam e fentanil, sem intercorrências. A apresentação deste caso tem como objectivo realçar as dificuldades inerentes ao diagnóstico de actinomicose com frequente necessidade de procedimentos invasivos, sob anestesia geral, o que condiciona um risco anestésico importante associado à dificuldade na abordagem da via aérea.

Bronchial Asthma in Children: Clinical and Epidemiologic Approach in Different Portuguese Speaking Countries

BACKGROUND: Geographical differences in asthma prevalence are currently accepted, but evidence is sparse due to the lack of multicentre studies using the same protocol. OBJECTIVES: To compare the prevalence of asthma and atopy among schoolchildren from Portuguese speaking countries (ISAAC and Portuguese Study) and evaluate some environmental variables, such as house dust mite exposure. MATERIAL AND METHODS: Significant random samples of schoolchildren studied with standard validated methods--questionnaires, skin prick tests, methacholine bronchial challenge tests; dust bed sampling for analysis of mite antigens. RESULTS: In the ISAAC study, in the 13-14 year-old age group, statistical significant differences were found, with higher wheezing prevalence in Brazil than in Portugal (two-fold). In the Portuguese Study, atopy prevalence ranged between 6.0 and 11.9% in Sal and S. Vicente (Cape Verde), up to 48.6 and 54.1% in Macau and Madeira. Active asthma had the higher values in Madeira (14.6%), and the lower in Macau (1.3%). Cape Verde had intermediate asthma prevalence (10.6 and 7.0%). The bronchial challenge test was positive in 25, 66 and 70% of asthmatic children from Sal, S. Vicente and Madeira respectively. Significant HDM antigen concentrations (Der p1) were found in Cape Verde and Madeira. CONCLUSIONS: There are significant variations in asthma and atopy prevalence between these pediatric populations. The reasons remain under discussion, but genetics linked to race, seem to play a central role, modulated by environmental and lifestyle variables.

Nursing Home-Acquired Pneumonia Presenting at the Emergency Department

Nursing home-acquired pneumonia (NHAP) is one of the most common infections arising amongst nursing home residents, and its incidence is expected to increase as population ages. The NHAP recommendation for empiric broad-spectrum antibiotic therapy, arising from the concept of healthcare-associated pneumonia, has been challenged by recent studies reporting low rates of multidrug-resistant (MDR) bacteria. This single center study analyzes the results of NHAP patients admitted through the Emergency Department (ED) at a tertiary center during the year 2010. There were 116 cases, male gender corresponded to 34.5 % of patients and median age was 84 years old (IQR 77-90). Comorbidities were present in 69.8 % of cases and 48.3 % of patients had used healthcare services during the previous 90 days. In-hospital mortality rate was 46.6 % and median length-of-stay was 9 days. Severity assessment at the Emergency Department provided CURB65 index score and respective mortality (%) results: zero: n = 0; one: n = 7 (0 %); two: n = 18 (38.9 %); three: n = 26 (38.5 %); four: n = 30 (53.3 %); and five; n = 22 (68.2 %); and sepsis n = 50 (34.0 %), severe sepsis n = 43 (48.8 %) and septic shock n = 22 (72.7 %). Significant risk factors for in-hospital mortality in multivariate analysis were polypnea (p = 0.001), age ≥ 75 years (p = 0.02), and severe sepsis or shock (p = 0.03) at the ED. Microbiological testing in 78.4 % of cases was positive in 15.4 % (n = 15): methicillin-resistant Staphylococcus aureus (26.7 %), Pseudomonas aeruginosa (20.0 %), S. pneumoniae (13.3 %), Escherichia coli (13.3 %), others (26.7 %); the rate of MDR bacteria was 53.3 %. This study reveals high rates of mortality and MDR bacteria among NHAP hospital admissions supporting the use of empirical broad-spectrum antibiotic therapy in these patients.